Universal cannula seal

ABSTRACT

A medical device can include a housing, a first seal structure, and a seal expander. The first seal structure can have a proximal end and a distal end, and a side wall surrounding and defining an interior chamber. A seal wall can be connected to the side wall and include an expandable opening. A seal expander can be coupled to the housing, and can be at least partially in the interior chamber of the first seal structure. The seal expander can include an expandable neck portion and a seal interface portion, the seal interface portion being near an intersection of the side wall and the seal wall.

CLAIM OF PRIORITY

This application is a continuation of and claims the benefit of priorityunder 35 U.S.C. § 120 to U.S. patent application Ser. No. 17/224,017,filed on Apr. 6, 2021, which is a continuation of and claims the benefitof priority under 35 U.S.C. § 120 to U.S. patent application Ser. No.15/592,910, filed on May 11, 2017, which claims the benefit of priorityunder 35 U.S.C. § 119(e) to U.S. Provisional Patent Application Ser. No.62/335,980, filed on May 13, 2016, each of which is incorporated byreference herein in its entirety.

TECHNICAL FIELD

This document relates generally to medical devices, and moreparticularly, to systems, devices and methods for sealing an opening ina body during a surgical procedure.

BACKGROUND

Certain surgical procedures, such as minimally-invasive or laparoscopicsurgery, can involve delivery of an insufflation of a gas into the body.For example, in a laparoscopic procedure, an insufflation gas can bedelivered to the peritoneal cavity of a patient to distend the abdomenand improve visual and physical access to internal organs in theabdomen. Distension of the patient's abdomen can provide sufficientoperating space enable adequate visualization of the structures andmanipulation of instruments inside a patient.

It is important to maintain a sealed system to maintain insufflationduring a surgical procedure. For example, the interface between surgicalequipment and an access orifice in the patient's body must be sealed toavoid or reduce leakage of insufflation gas so that insufflation can bemaintained.

In a laparoscopic procedure, one or more cannulas are typically used toa deliver surgical tools into a body cavity. A cannula seal can be usedto provide a seal between the cannula an outer surface of an instrumentshaft that is connected to surgical tool to avoid or reduce leakage ofinsufflation gas through the cannula during the procedure. The cannulaseal is a critical component for surgery in the abdomen, because withoutit there is no insufflation, and without insufflation surgery cannot beeffectively carried out.

U.S. Pat. No. 6,945,983 discloses a sealing device with a variablecentral opening.

U.S. Pat. No. 5,209,737 discloses an elastomeric septum that is disposedin a trocar channel and includes portions which define an orificehaving, in a relaxed state a first cross-sectional area, and anactuation assembly provided with levers which pivot radially outwardlyto expand the seal and thereby expand the orifice to a secondcross-sectional area in response to entry of the instrument into thechannel.

SUMMARY

An example medical device seal assembly can include a housing, a firstseal inside at least part of the housing, and a plurality of elongatedsegments that extend into the first seal. The first seal can include aside wall that surrounds and defines an interior chamber, an expandableportion that joins a distal end of the side wall, and a first opening ata proximal end of the interior chamber. The first seal can furtherinclude an expandable seal opening in the expandable portion, an axis ofthe interior chamber being defined between the first opening and theexpandable seal opening.

The plurality of elongated segments can extend distally into theinterior chamber of the first seal. Each elongated segment can include aproximal portion, a middle portion, and a distal tip. Each elongatedsegment can extend from the proximal portion of the elongated segment,into the interior chamber of the seal and toward the axis of theinterior chamber to the middle portion, and then further into theinterior chamber and away from the axis of the interior chamber to thedistal tip of the elongated portion. Each distal tip of each of theplurality of elongated segments can be positioned on or near the sidewall of the first seal. In some examples, the plurality of elongatedsegments can be arranged concentrically around the axis of the interiorchamber. In some examples, each of the elongated segments can furtherinclude at least one flange that is connected to the distal tip andextends inward toward the chamber axis.

The plurality of elongated segments can converge at the middle portionto define a neck, the neck having a minimum internal neck dimension. Theminimum internal neck dimension can be sized less than a selected outercross-sectional dimension of an instrument shaft, such that, when theinstrument shaft is inserted through the elongated segments, theinstrument shaft biases the elongated segments away from the axis of theinterior chamber to press against the side wall of the first seal andexpand the expandable portion of the first seal and the seal opening.

In some examples, each of the elongated segments has a segment length ina proximal to distal direction and a segment width that varies along thelength of the elongated segment. A minimum segment width can, forexample, be at the middle portion of the elongated segment, and amaximum segment width can be in the proximal portion of the elongatedsegment.

The medical device seal assembly can further include a second sealdistal of the first seal. The medical device seal assembly can alsofurther include an extraction guide between the first seal and thesecond seal. The extraction guide can include including adistally-facing concave surface and an extraction guide opening in thedistally-facing concave surface. The extraction guide opening can bealigned with the expandable seal opening in the first seal.

An example medical device can include a housing, a first seal structureat least partially inside the housing, and a seal expander. The firstseal structure can include a proximal end and a distal end, and a sidewall surrounding and defining an interior chamber, and a seal wallconnected to the side wall. The first seal structure can further includea first opening at a proximal end of the side wall, and an expandableopening in the seal wall. An axis of the interior chamber can be definedbetween the first opening and the expandable opening.

The seal expander can be coupled to the housing and at least partiallyin the interior chamber of the first seal structure. The seal expandercan include an expandable neck portion and a seal interface portion. Theseal interface portion can be near an intersection of the side wall andthe seal wall. In some examples, the seal interface portion caninterface with the side wall of the first seal structure at an angleperpendicular to the axis or perpendicular to the side wall.

In some examples, the medical device can have a first state and a secondstate, where in the first state, the neck portion of the seal expanderis in an expanded state to accommodate a shaft portion of an instrument,the neck portion having an one or more internal surfaces defining aninternal profile having an expanded internal size to accommodate anouter surface of the shaft of the instrument, the seal interface portionof the seal expander being pressed against the side wall of the firstseal structure, and the expandable opening in the seal wall beingexpanded to an expanded opening size. In a second state, the neckportion of the seal expander is in a neutral state, the internalsurfaces of the neck portion defining an internal surface profile havinga neutral internal size that is smaller than the expanded internal size,and the expandable opening in the seal wall having a second opening sizethat is smaller than the expanded opening size.

In some examples, the medical device can further include a second sealstructure coupled to the housing, and an extraction guide inside thesecond seal structure, at least a portion of the first seal structureextending inside the extraction guide. The extraction guide can includea distally-facing surface that is distal of the expandable opening inthe seal wall of the first seal structure, and an extraction guideopening in the distally-facing surface. The extraction guide opening canbe aligned with the axis. The distally-facing surface can includeportions sized and shaped to guide an object to the extraction guideopening.

In some examples, the seal expander includes a plurality of elongatedelements that extend distally into the first seal structure, converge toform the neck portion, and extend from the neck distally and outwardlyaway from the axis, each of the elongated elements having one or moredistal surfaces, the seal interface portion of the seal expanderincluding the one or more distal surfaces on the elongated elements.

An example medical device includes a first seal having a side wall, aseal portion connected to the side wall, an interior chamber defined bythe side wall, and a seal opening defined in the seal portion, and aplurality of elongated segments extending into the interior chamber ofthe first seal. The plurality of elongated segments can extend toconverge at an intermediate neck, and then extend further to diverge ata distal mouth. Expansion of the intermediate neck can bias distal endsof the elongated segments radially outward against the side wall of thefirst seal and increase the size of the seal opening. A differencebetween the seal opening diameter and the neck inner diameter can definea seal offset dimension. In some examples, the plurality of elongatedsegments are sized and shaped to provide a consistent offset dimensionseal offset dimension through a range of expanded states to accommodatea range of sizes of shafts inserted through the plurality of elongatedsegments.

The medical device can optionally further include base portion, each ofthe plurality of elongated segments being coupled to the base portion byone or more hinge portions, the plurality of elongated segments pivotingat the one or more hinge portions when the neck is expanded.

The medical device can optionally further include a cannula cap, acannula coupled to the cannula cap, a second seal at least partially inthe cannula, and an extraction guide at least partially in the secondseal, the first seal being at least partially in the extraction guide.In some examples, the seal opening is circular and has a seal openingdiameter, and the intermediate neck defines a circular opening having aneck inner diameter, the seal opening diameter being smaller than theneck inner diameter.

In some examples, the medical device can include a first state and asecond state. In the first state, the plurality of elongated segmentsand the seal portion are in an expanded state to accommodate a shaftportion of an instrument, a difference between an expanded seal openingdiameter and the neck inner diameter defining a first state offsetdimension. In the second state, the plurality of elongated segments andthe seal portion are in a neutral state, a difference between a neutralseal opening diameter and the neck inner diameter defining a secondstate offset dimension, the first state offset dimension beingapproximately the same as the second state offset dimension.

A method of sealing two instruments having different sized shaft in acannula seal can include receiving into a cannula a first instrumenthaving a first shaft of a first cross-sectional outer diameter, andreceiving the instrument shaft into a neck portion of a seal expander, across-sectional dimension of an opening in the cannula seal beingsmaller than a cross-sectional opening in the neck portion of the sealexpander by an offset dimension. The method can further include biasingouter portions of the seal expander against a side wall of a cannulaseal to expand an opening in a cannula seal to accommodate the firstcross-sectional outer diameter, without changing the offset dimension,and receiving the first shaft into the cannula seal and sealing againstan outer surface of the first shaft.

The method can optionally further include, after the first instrument isremoved from the cannula seal, receiving into the cannula a secondinstrument having a second shaft of a second cross-sectional outerdiameter that is different than the first cross-sectional outerdiameter, receiving the second shaft into the neck portion of the sealexpander, and biasing the outer portions of the seal expander againstthe side wall of the cannula seal to expand the opening in a cannulaseal to accommodate the second cross-sectional outer diameter, withoutchanging the offset dimension.

In some examples, receiving an instrument shaft into a neck portion of aseal expander can include receiving an instrument shaft into a neckopening defined by a plurality of elongated segments that form the sealexpander, the opening being smaller than the cross-sectional outerdiameter of the first instrument shaft, and wherein, biasing outerportions of the seal expander against the side wall includes deflectingthe elongated segments outwardly against the side wall of the cannulaseal. In some examples, expanding the cannula seal includes stretching aportion of the cannula seal to enlarge an opening in the cannula seal,and receiving the first shaft into the cannula seal includes receivingthe first shaft through the opening in the cannula seal.

Each of these non-limiting examples can stand on its own, or can becombined in various permutations or combinations with one or more of theother examples.

This Summary is intended to provide an overview of subject matter of thepresent patent application. It is not intended to provide an exclusiveor exhaustive explanation of the invention. The detailed description isincluded to provide further information about the present patentapplication.

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings, which are not necessarily drawn to scale, like numeralsmay describe similar components in different views. Like numerals havingdifferent letter suffixes may represent different instances of similarcomponents. The drawings illustrate generally, by way of example, butnot by way of limitation, various embodiments discussed in the presentdocument.

FIG. 1A is an illustration of an example instrument system for use inrobot-assisted minimally invasive surgery.

FIG. 1B is an illustration of an example physician console for use inrobot-assisted minimally invasive surgery.

FIG. 1C is an illustration of an example control cart for use inrobot-assisted minimally invasive surgery.

FIG. 2A is a perspective view of an example expandable seal assemblywith an instrument shaft inserted through the assembly.

FIG. 2B is an illustration of an expandable seal assembly utilized in aminimally-invasive surgical procedure.

FIG. 3A is a perspective view of an example seal assembly.

FIG. 3B is a top perspective view of an example seal assembly.

FIG. 3C is an exploded view of an example seal assembly.

FIG. 3D is a top view of an example seal assembly.

FIG. 3E is a perspective cross-sectional view of an example sealassembly.

FIG. 3F is a cross-sectional view of an example seal assembly.

FIG. 3G is an enlarged cross-sectional view of a portion of the sealassembly of shown in FIG. 3F.

FIG. 4A is a perspective view of an example seal expander.

FIG. 4B is a conceptual illustration of an end view of the example sealexpander shown in FIG. 4A.

FIG. 4C is a top view of the example seal expander shown in FIG. 4A.

FIG. 4D is a bottom view of the example seal expander shown in FIG. 4A.

FIG. 4E is an illustration of an example configuration of an elongatedsegment of a seal expander and a portion of a wiper seal.

FIG. 5A is a perspective view of a seal expander connected to a cap.

FIG. 5B is a side view of an example first seal that can interact with aseal expander as part of an expandable seal assembly.

FIG. 5C is a top perspective view of an example first seal that caninteract with a seal expander as part of an expandable seal assembly.

FIG. 5D is a perspective cross-sectional view of an example sealassembly.

FIG. 6A is a perspective cross-sectional view of an example sealassembly without a retraction guide.

FIG. 6B is a perspective cross-sectional view of an example sealexpander with flanges in a neutral position.

FIG. 6C is a perspective cross-sectional view of an example sealexpander with flanges in a distally-deflected position.

FIG. 7 is a cross-sectional view of an example seal assembly with anelongated first seal.

FIG. 8 is a cross-sectional view of an example seal assembly without afirst seal between the expander and retraction guide.

FIG. 9 is a cross-sectional view of an example seal assembly that doesnot have a retraction guide.

FIG. 10 is a cross-sectional view of an example seal assembly that has astraight-walled expander.

FIG. 11A is a top view of an example seal assembly.

FIG. 11B is a bottom perspective view of an example seal assembly.

FIG. 11C is a partial cross-sectional view of the example seal assemblyshown in FIGS. 11A and 11B.

DETAILED DESCRIPTION

A cannula seal that can accommodate a range of instrument shaft sizescan be used in a laparoscopic surgical procedure. During a laparoscopicsurgery procedure in the abdomen, for example it is important that theabdomen be distended to provide space to for operation of visualizationtools and surgical tools. An expandable cannula seal can be used todeliver visualization tools and surgical tools and maintain insufflationduring the procedure. A cannula seal is a critical component formaintaining insufflation during minimally-invasive surgery orlaparoscopic surgery: Without it there is no insufflation, and withoutinsufflation, surgical procedure cannot be effectively carried out.Temporary loss of pressure during certain portions of the procedure isnot catastrophic, as more insufflation gas can be delivered toreestablish insufflation, but preservation of insufflation is generallyneeded during the manipulation of tools as the procedure is carried out.

In some surgeries, it is desirable to exchange tools during theprocedure. Exchanging tools during a procedure presents a problem, asseals are frequently designed to accommodate a particular shaft size. Amismatch between tool size and seal size can create procedural problems,such as damage to the seal or insufflation gas leaks. But switching outa cannula seal to accommodate a tool change during a procedure can betime consuming and inconvenient.

A universal cannula seal, i.e., a seal that can accommodate a range oftool sizes, can be provided to avoid the need to change the cannula orcannula seal during a procedure. For example an expanding seal assemblycan include a seal, such as a wiper seal, and mechanism to that changethe size of an opening in the seal, to maintain an effective seal withdifferent sized instrument shafts.

An expanding seal assembly can include, for example, a cannula seal anda seal expander that has elements that expand a seal opening based uponthe size of tool that is inserted into portion of the seal expander,such as a neck. A deflectable structure that is contacted by an outersurface of an instrument shaft can be connected or otherwise linked to astructure that contacts a portion of a seal structure. Insertion of theinstrument shaft into the medical device assembly can causes movement ofthe deflectable structure, which in turn can expand an opening in theseal structure.

In an example, a plurality of elongated elements extend through themedical device assembly in an insertion direction, and converge at afirst location to form a first inner cross-section at which an outersurface of an instrument shaft contacts inner surfaces of the elongatedelements. The elongated elements can diverge from the first location andextend to a second location at which the elements interact with the sealstructure. Expansion of the first location by an instrument shaft cancause a corresponding expansion at the second location, which can expandan opening in the seal structure. In an example, the elongated elementscan provide an approximately one-to-one expansion ratio, e.g. a onemillimeter displacement of an element at the first location causes a onemillimeter displacement at the second location. Other expansion ratiosare possible.

An expanding seal assembly can be used with a surgical system thatincludes tools that allow a physician to see and manipulate tissue (orother objects or materials) inside a patient's body, using controlssituated outside the patient's body. Visualization tools can, forexample, include optical tools, such as fiber optic cameras, orelectronic tools, such as digital cameras or sensors. Surgical tools caninclude, for example mechanical or electromechanical tools such asneedle drivers, suture tools, retraction instruments, clip appliers,probes fenestrated graspers, or cardiac stabilizers. Surgical tools canalso include energy instruments such as monopolar or biopolar tools,ultrasonic tools, or lasers, which can be used for cautery or ablation,for example. Tools can be coupled to a computer system andelectromechanical manipulators to provide precision and ease of use fora physician or clinical personnel. The use of such systems is sometimesreferred to as a robot-assisted minimally invasive surgery.

FIGS. 1A, 1B, and 1C illustrate an example robot-assisted minimallyinvasive surgical system. FIG. 1A shows an instrument system 100(sometimes known as a “patient side cart”) that can be situated near apatient operating table (not shown). FIG. 1B shows a surgeon console 150that can include controls and a viewing system. FIG. 1C shows a controlcart 180 that can include, for example, processing equipment andcommunication equipment.

Referring again to FIG. 1A, the system 100 can include a base 102, asupport tower 104, and one or more manipulator arms 110, 111, 112, 113,which can be mounted on the support tower. Alternatively, themanipulator arms 110, 111, 112, 113 can be connected to a main boom (notshown), which can be movable. An instrument 130 can be mounted to aninstrument mount 120 on one of the manipulator arms. A cannula (notshown in FIG. 1A) can be mounted to a cannula mount. An instrument 130can be inserted through a cannula seal in the cannula, and into thepatient (not shown) for use in a surgical or other medical procedure.Through movement of the manipulator arms, the orientation of theinstrument can be controlled in multiple dimensions, e.g. lateral,horizontal, vertical, angular movements in one, two, or three planes.

FIG. 1B shows an example physician console 150. The physician consolecan include hand control 155, 156 and pedal controls 160, 161. The handcontrols 155, 156, and pedal controls 160, 161 can be used to controlequipment at the patient side cart. For example, portions of a distalend of an instrument can be manipulated using instrument controls. Thecontrols can include haptic feedback features so that a physician caninterpret physical information, such as resistance or vibration, throughthe controls. The physician console 150 can also include a viewingsystem 165 that can display video or other images of a surgical site.

FIG. 1C shows an example control cart 175. The control cart can includeprocessing equipment 180 for processing controls, facilitatingcommunication between the physician console and the patient side cart,or a remote site. The control cart 175 can also include a display 190,which can show images that the physician is seeing on the physicianconsole, a video feed from a camera in the patient, or otherinformation. In an example configuration, signals input at a surgeonconsole 150 (also “physician console 150”) can be transmitted to theequipment 180 on the control cart, which can interpret the inputs andgenerate commands that are transmitted to the system 100 to causemanipulation of an instrument 130 or portions of a manipulator arm 110.The equipment 180 is shown on a cart for exemplary purposes, but couldalso be arranged in various configurations, e.g., it could be integratedas part of the physician console, the patient side cart, or both, ordivided between the physician console and patient side cart. Theequipment can also be provided as software, hardware, or both, on aninstalled or remote system.

FIG. 2A and FIG. 2B show an example of an expandable cannula seal withina cannula 205 in a minimally invasive surgery system. An instrumentshaft 210 can be inserted into through a cannula seal assembly, whichincludes an expandable cannula seal. The cannula seal can prevent orreduce leakage around the instrument shaft 210.

FIG. 2B shows the cannula 205 utilized in a single site surgicalapproach, where multiple instrument shafts can be inserted throughcannulas 215, 220 that are inserted through a single incision site inthe skin 230, such as through the navel. A tool such as an end effectoror a visualization device can be situated on a distal end of aninstrument shaft that is inserted through an expandable cannula seal. Anend effector utilized in the surgical system can be a jawed surgical endeffector, such as a scissors, grasping retractor, or needle driver, forexample. A visualization device can be a digital video camera orendoscope, for example. An expandable cannula seal can allow forexchange of instruments during the procedure without changing thecannula seal, even if the instruments require or include shafts ofvarying dimensions, because the cannula seal can expand to accommodatedifferent shaft sizes.

FIG. 3A-3F show an example medical device seal assembly 300 that caninclude an expandable seal that accommodates a range of instrumentsizes. The medical device seal assembly 300 can include a cap 305, aseal expander 310, a first seal 315, a retraction guide 320, a clip 325,a second seal 330, and a housing 340. Elongated segments 391, 392, 393,394, 395, 396 on the seal expander 310 can be deflected by outersurfaces of an instrument shaft. The elongated segments 391, 392, 393,394, 395, 396 can stretch the first seal 315 to expand an opening in theseal, to accommodate insertion of an instrument shaft through the sealassembly 300.

The seal expander 310, first seal 315, retraction guide 320, second seal330, and housing 340 can be assembled, from proximal to distal (shown inthe exploded view provided in FIG. 3C), with each part fitting at leastpartially into the next part, i.e. the seal expander 310 can at leastpartially be inserted into the first seal 315, which can be insertedinto the retraction guide 320, which can be inserted into the secondseal 330, which can be inserted into the housing 34. The components canbe held together by the cap 305 and clip 325. In some examples, themedical device seal assembly can include a subset of the parts shown inFIGS. 3A-3F. For example, the retraction guide 320 could be omitted, asshown in FIG. 8 , FIG. 9 , and FIG. 10 , or the second seal 330 could beomitted.

The cap 305 can include an opening 306 and a label 307 that indicates arange of sizes (e.g. 5-14 mm) that are compatible with the expandableseal system. The cap can be formed of a rigid material, such aspolycarbonate.

The seal expander 310 can include a proximal opening 311, an expandableneck portion 312, and a distal mouth 313. The seal expander can, forexample, be formed of polycarbonate. The seal expander 310 can alsoinclude an expander proximal lip 314 that can rest or seal against thecap 305. Inner surfaces 349 of the seal expander 310 can be shaped toact as an insertion guide to guide a tool into the seal expander. Forexample, the inner surfaces can be shaped like a funnel that extendsfrom a proximal opening 318 a to neck portion 312 of the seal expander310.

The neck portion 312 of the seal expander 310 can expand when aninstrument shaft is inserted into the neck. In an example, the neckportion can expand so that an expanded inner diameter of the neckportion 312 matches an inner diameter of the proximal opening 318 a.

The first seal 315 (also shown in FIGS. 5B and 5C) can include a sidewall 317 that defines an interior chamber 319. The distal opening 318 bcan be sized and shaped to seal against an instrument shaft insertedthrough the opening. The first seal 315 can, for example, be a wiperseal. The side wall 317 can be define portions of a cylinder, frustum,curve-walled funnel, bell-shaped flare, or polygonal prism, for example.The first seal 315 can also include portions that define a proximalopening 318 a and a distal opening 318 b, which together define an axis318 c of the interior chamber 319. The first seal can also includeproximal lip 316 sized and shaped to rest or seal against the proximallip 314 of the seal expander, against the cap 305, or against both thecap 305 and the proximal lip 314. For example, the proximal lip 314 ofthe seal expander 310 and the proximal lip of the first seal 315 can beshaped as rings with overlapping diameters, i.e. the outer diameter ofthe proximal lip 314 of the seal expander 310 can be larger than theinner diameter of the proximal lip 316 of the first seal 315 so that therings overlap. The first seal can be made, for example, of polyisoprene,with a durometer of 37 to 48. The side wall 317 of the first seal 315can vary in thickness proximally to distally. For example, a proximalportion can be relatively thick, e.g. 1-2 mm, to provide strength nearthe proximal lip. A distal portion 354 that forms the distal opening 318b can be relatively thin, e.g. less than 0.1 mm, to allow the seal tostretch and expand the distal opening 318 b.

The medical device seal assembly 300 can also include an extractionguide 320. The extraction guide can, for example, be formed of lowdensity polyethylene (LDPE). The extraction guide can include a proximalopening 322, walls sized and shaped to define an interior chamber thatcan receive the first seal, and a distal opening 321. The extractionguide can include one or more inwardly tapered or concave distalsurfaces 323 that can guide awkwardly-shaped objects, such as gauze ortissue, or other object such as tools, to the distal opening 321 duringretraction. For example, the extraction guide can include adistally-facing surface that be can be a conical surface, and theextraction guide distal opening can be at the center of the cone. Thedistally-facing surfaces can also be curved surfaces converging to theextraction guide distal opening 321.

The retraction guide 320 can include flanges or teeth 324 that form thetapered or concave distal surfaces. The teeth 324 can deflect or benddistally to accommodate insertion of an instrument that is larger thanthe distal opening in the extraction guide. The teeth 224 can return totheir original configuration—defining a tapered or concave surfaces—whenthe instrument shaft 353 is withdrawn. When returned to the tapered orconcave shape, the extraction guide can prevent snagging of an object,such as gauze, on the elongated members of the seal expander 310, whenthe object is pulled by a shaft through the assembly. The retractionguide 320 can at least partially fit inside the second seal 330, asshown in FIG. 3E.

The second seal 330 can be a “zero seal” that seals when no instrumentin present in the seal assembly. The second seal can be a duck billseal, for example, or a four-lipped “double duck bill” seal as shown inFIG. 3C. The second seal can also be a flapper valve (not shown), whichcan optionally be connected to a mechanism such as a lever or buttonthat can be operated by a user to bias (i.e. opened and shut) theflapper valve.

The medical device seal assembly 300 can include a housing 340 that caninclude an O-ring for sealing with a sleeve or tube component (notshown). The housing can also include a gas port 345 which can be usedfor insufflation, and a manual valve 335 that can control the flow ofgas through the gas port.

A clip 325 can connect to the housing 340 and the cap 305 to retain thecomponents in an assembled configuration.

The openings in the cap 305, seal expander 310, first seal 315,retraction guide 320, and second seal 330 can be aligned with the axis318 c, so that an instrument can be received through the seal assembly300, as illustrated in FIG. 2A. When an outer dimension (e.g.,circumference) of an inserted instrument shaft is larger than an insidedimension of the neck portion 312 of the seal expander, the neck portion312 of the seal expander can expand to accommodate the instrument.

Instrument shafts are typically circular in cross section. In anexample, inner surfaces of the seal expander define a neck dimensiondiameter. When the outer diameter of an instrument shaft is larger thanthe inner diameter of the neck portion 312, the seal expander 310 canexpand to a diameter that matches the outer diameter of the instrumentshaft. For example, the inner diameter of the neck portion can be 5millimeters (mm), and can be expandable up to 14 millimeters toaccommodate a wide range (5-14 mm) of instrument shafts. The openings inthe seal expander and seal can also be shaped as ovals, polygons(optionally with rounded corners) or other shapes, to accommodatesimilarly-shaped instrument shafts. The outer dimension of an insertedinstrument can, for example, be the maximum dimension of non-circularshape, or a length of a major axis of an elliptical cross-section.Portions of the seal expander, such as fingers, can beindividually-deflectable, so that the neck portion shape can change tomatch the shape and dimensions of a shaft.

As shown in FIGS. 3E and 3F, and 3G, one or more distal outer surfaces350 of the seal expander can interact with one or more inner surfaces351 the first seal and cause the distal opening 318 b to expand when ashaft is inserted through the neck portion 312 of the seal expander 310.The seal expander 310 can, for example, be sized and shaped so that asthe neck portion expands, the distal opening 318 b in the seal 315 isalways smaller than the opening in the neck portion. This can assurethat the seal 315 remains in contact with an outer surface of aninstrument shaft that expands the neck portion 312 to the size ofinstrument shaft.

As shown in FIG. 3G, when an instrument shaft 353 that is larger than anopening 352 defined by the neck portion 312 of the seal expander 310,the outer surfaces 350 of the seal expander can define a seal interfaceportion 359 that can convey expansion forces on the one or more innersurfaces 351 of the first seal 315, which expands the size of the distalopening 318 b in the first seal 315. The seal expander 310 and firstseal 315 can be sized and shaped so that, as the distal opening isexpanded, a sealing relationship is maintained between the instrumentshaft 353 and the portions 354 of the first seal 315 that form thedistal opening 318 b.

In an example embodiment, in a neutral position, a diameter of thedistal opening 318 b in the first seal 315 can be slightly smaller, byan “offset dimension” than the diameter of the neck portion. This offsetarrangement can assure that the instrument shaft 353 contacts theportions 354 of the first seal 315 that form the distal opening 318 b,when the opening is expanded by the seal expander 310.

In another example, the seal expander can be sized and shaped so thatthe offset dimension changes, but is always positive as the distalopening expands through a range (e.g. 5-14 mm) of accommodated shaftsizes. In an example, the seal expander 310 and first seal 315 can besized and shaped so that the offset dimension is constant, or is largerthan a minimum value, as the seal expander expands the first seal 315 toaccommodate an instrument shaft 353.

In an example embodiment, the seal expander can include a number ofelongated segments or “fingers” 391, 392, 393, 394, 395, 396. Asillustrated in Fib. 3B, the seal expander can, for example, include sixelongated segments. The elongated segments can be about 0.03 inch (0.8mm) thick, for example. Seal expanders with fewer or more elongatedsegments are also possible. For example, a seal expander with three,four or five segments is possible, and seal expanders with up to ten ormore segments are also possible.

Each elongated segment 391, 392, 393, 394, 395, 396 can have a proximalportion 381, a middle portion 382, and a distal tip 383. In an example,each elongated segment of the plurality of elongated segments extendsfrom the proximal portion 381 into the interior chamber 319 of the firstseal 315, and toward the axis 318 c of the interior chamber to themiddle portion 382 of the elongated segment, and then further into theinterior chamber 319 and away from the axis 318 c of the interiorchamber to the distal tip 383 of the elongated segment. Each distal tip383 of each of the plurality of elongated segments can be positioned onor near the side wall 317 of the first seal 315. In an example, aninstrument shaft can bias the elongated segments 391, 392, 393, 394,395, 396 away from the axis 318 c, which pushes the distal tips againstthe side wall 317 of the first seal and expands the distal opening 318 bto accommodate the instrument shaft 353.

The distal mouth 313 of the seal expander can include flanges 361, 362,363 that can extend inward from distal ends of the elongated segments,toward the axis 318 c. The flanges can also converge distally, i.e.extend both toward the axis 318 c and distally toward the distal end ofthe first seal 315.

The flanges 361, 362, 363 can support the seal 315 during retraction ofan instrument, for example to avoid stretching of the seal as aninstrument is retracted. In an example, the flanges 361, 362, 363 canreduce friction during retraction by providing structural support thatprevents the seal from pulling or wrapping on an instrument shaft duringretraction. In an example, the seal assembly provides for approximatelyconsistent friction forces during insertion and retraction. The flangescan, for example, assure that the surface area of the seal 315 that isin contact with an instrument shaft during withdrawal is approximatelythe same as the surface area that is in contact with the instrumentshaft during insertion. Without the flanges on the seal expander 310,the instrument shaft could, for example, pull the first seal 315proximally as the shaft is withdrawn, which can increased frictionalforces, due to increased surface area between the shaft and seal 315.

FIGS. 4A-4D are show an example seal expander 410 that can be part of anexpandable seal assembly, such as the seal assembly 300 illustrated inFIGS. 3A-F. FIG. 4A is a perspective view of an example seal expander410. FIG. 4B is a conceptual illustration that shows a shape ofinstrument contacting surfaces 460 a, 460 b, 460 c, 460 d, 460 e, 460 fon a neck portion 412 of the seal expander 410 in a neutral state and anexpanded state. The surfaces 460 a-f can be shaped so that in anexpanded state they align with a circle 420 having a diameter D1, whichcan, for example, be the diameter of the largest compatible instrumentshaft 450 for the expandable seal assembly. In a neutral state, thesurfaces 460 a-f can be tangent with a circle 421 having a diameter D2that is smaller than D1.

FIG. 4C is a top view of the seal expander 410 and illustrates anarrangement similar to FIG. 4B. The arrow 440 indicates the expansion ofelongated segment 491 to a maximum expanded state, at which point theradius of curvature 480 of the neck portion 412 matches the radius R_(i)of the circle 420 at the maximum expanded state.

FIG. 4D is a bottom view of the seal expander 410 in a neutral state.FIG. 4D shows that the radius of curvature of the outer surface 425 ofthe elongated segment 491 matches the radius R_(o) of a circle 430 atthe maximum expanded state of the elongated segment 491.

FIG. 4E illustrates an example configuration of the seal expander 410and seal 415. An elongated segment 491 has a neck portion 412 that, in aneutral position has inner surfaces having a minimum dimension. Anneutral offset dimension O_(n) can be defined between the neck portion412 and the wiper portion 470. When an instrument is inserted in theseal assembly, it deflects the elongated segment 491′ to a deflectedposition, at which point an expanded offset dimension O_(e) can bedefined between the neck portion and the wiper portion. In an example,the expanded offset dimension O_(n) is approximately the same as theneutral offset dimension O_(n). In another example, the expanded offsetdimension is within a predetermined percentage of the neutral offsetdimension (e.g. within 10%, within 15%, or within 20% of the neutraloffset dimension.)

FIG. 5A shows an example in which a seal expander 510 is connected to acap 505. For example, a seal assembly can be provided that includes thecap 505 and seal expander 510 as a single piece. The example sealexpander 510 is shown with ten elongated segments, but seal expanderscould include more, or fewer elongated segments.

FIG. 5B is a side view of an example first seal 515 that includes a lip516 and an interrupted cinch 570. The interrupted cinch 570 can providecircumferential strength to provide tension during expansion of the seal515. The tension can, for example, assure that an effective seal ismaintained against an instrument shaft inserted through opening in theseal.

FIG. 5C is a perspective top view of the first seal 515 that shows theproximal opening 518 a and distal opening 518 b which can define an axis518 c, shown in FIG. 5B.

FIG. 5D is a perspective cross-sectional view of an example sealassembly 500 that shows the cap and seal expander 510 assembled with thefirst seal 515, a retraction guide 520, second seal 530, and housing540. The retraction guide 520 can have a plurality of teeth 522 that canguide an awkwardly-shaped object such as gauze to the distal opening 51in the first seal 515. The seal guide can have a number of elongatedsegments or “fingers” 591, 592, 593, 594 (and additional segments thatare not shown in the cross-section) that can expand when an instrumentis inserted into the seal assembly 300, which biases the distal ends595, 596 of the elongated members against the seal 515 and expands thedistal opening 521.

FIG. 6A is a cross-sectional view of another example expandable sealassembly 600 that include a cap 605, seal expander 610 having elongatedsegment 691, 692, a first seal 615, retraction guide 620, second seal630, and housing 640. The seal expander 610 in this example has fourelongated segments, two of which 691, 692 appear in the cross-sectionfigure. The elongated segments converge to define a neck portion 612.Inner surfaces at the neck portion define a neck diameter.

FIG. 6B and FIG. 6C show the seal expander 610 in a first state and asecond state. In the first state, the flanges 681, 682, 683, 684, 685,686 are in a neutral position. In the second state, shown in FIG. 6C,the flanges 681, 682, 683, 684, 685, 686 are deflected distally toaccommodate an instrument (not shown) that is inserted through the sealexpander. When the instrument is larger than the diameter D1 defined bythe flanges, but smaller than the diameter D2 defined by inner surfaces641, 642 of the neck portion 612, the flanges deflect as the instrumentis inserted, as shown in FIG. 6C. When the instrument is larger than thediameter D2 of the neck portion (not shown), the elongated segments 691,692 deflect outward away from an axis 618 c of the seal expander.

FIG. 7 is a cross-sectional view of another example expandable sealassembly 700 that includes a seal expander 710, first seal 715,retraction guide 720, second seal 730, and housing 740. The first seal715 has a tapered portion 750 that decreases in radius distally. Theseal expander 710 has elongated segments that contact an inner surfaceof the first seal 715 proximal of the tapered portion 750. The taperedportion 750 of the first seal 715 can extend into the retraction guide720. When an object is retracted, the tapered portion 750 of the firstseal can invert, and extend proximally into the seal expander.

FIG. 8 is a cross-sectional view of example expandable assembly 800 thatincludes an expander 810 and a retraction guide 820. The expander caninclude a neck portion 812 and elongated segments 891, 892, 893, 894,895, 896. The retraction guide can include elongated segments, 881, 882,883, 884. The elongated segments can each define a pocket 885, 886 whichcan receive a distal end 861, 862 of the elongated segments 891, 892. Inan example, the elongated segments 881, 882, 883, 884 of the retractionguide can expand and retract with the elongated segments 891, 892, 893,894, 895, 896 of the expander. For example, when an instrument shaft(not shown) in inserted through the neck portion 812 of the expander,the elongated segments 891, 892, 893, 894, 895, 896 deflect away from anaxis 818 c of the expander. The expanded elongated segments 891, 892,893, 894, 895, 896 can push against the elongated segments 881, 882,883, 884 of the retraction guide and bias the elongated segments of theretraction guide away from the axis to accommodate the instrument shaft.The assembly 300 is shown in FIG. 8 without a seal between the expanderand the retraction guide. In another example, a seal can be added to theconfiguration shown in FIG. 8 , positioned between the expander and theretraction guide, with a sealing surface configured to seal against aninstrument shaft, as shown for example in FIG. 3C and FIG. 6A.

FIG. 9 is a cross-sectional view of an expandable seal assembly 900 thatincludes a seal expander 910 and a first seal 915. The seal can includea tapered portion 920 as explained above in reference to FIG. 7 . Inthis example, the assembly does not include a retraction guide. The sealexpander can include elongated segments 991, 992 that have distalsurfaces that flare outwardly away from an axis 918 c to define adistally-facing mouth 925. The distally-facing mouth can act as anextraction guide, to guide objects into the seal 915.

FIG. 10 is a cross-sectional view of an expandable seal assembly 1000includes a seal expander 1010 and a first seal 1015. The seal expander1015 can include elongated segments 1091, 1092 that vary in thicknessalong the length and define a neck portion 1012. The elongated segments1091, 1092 can have distal surfaces that define a distally-facing mouth1025. The distally-facing mouth can act as an extraction guide.

FIG. 11A is a top view of an example cap 1105 and seal expander 1110.FIG. 11B is a bottom partial perspective view of an example sealexpander 1110. FIG. 11C is a partial cross-sectional view of the exampleseal assembly shown in FIGS. 11A and 11B. The seal expander 1110 can beconnected to the cap 1105, or a fabricated separated piece that isdirectly or indirectly coupled to the cap 1105. The cap 1105 and sealexpander 1110 can be sized and shaped to accommodate a range of shaftsizes. For example the cap 1105 and seal expander shown in FIGS. 11A and11B can be sized and shaped to accommodate shafts or tool ranging from 5to 8 millimeters. The cap can include a label 1107 that indicates therange of sizes. The seal expander 310 can include a proximal opening1111, an expandable neck portion 1112, and a distal mouth 1113. In anexample, configuration, the proximal opening 1111, expandable neckportion 1112, and distal mouth 1113 can be shaped similar to thearrangement shown in FIGS. 3F and 3G. The seal expander can include aplurality of elongated segments or “fingers” 1130 a, 1130 b, 1130 c 1130d that can be deflectable to accommodate a shaft inserted through theseal expander and expand a seal (not shown) surrounding the sealexpander. In an example configuration, the elongated segments 1130 a,1130 b, 1130 c 1130 d can converge at the neck portion 1112 and flareoutward toward a mouth that is larger than the neck. The elongatedsegments 1130 a, 1130 b, 1130 c 1130 d can be have a radial thickness T₁that is larger at the neck 1112 than a thickness T₂ at the mouth 1113and larger than a segment thickness T₃ at the mouth.

The above detailed description includes references to the accompanyingdrawings, which form a part of the detailed description. The drawingsshow, by way of illustration, specific embodiments in which theinvention can be practiced. These embodiments are also referred toherein as “examples.” Such examples can include elements in addition tothose shown or described. However, the present inventors alsocontemplate examples in which only those elements shown or described areprovided. Moreover, the present inventors also contemplate examplesusing any combination or permutation of those elements shown ordescribed (or one or more aspects thereof), either with respect to aparticular example (or one or more aspects thereof), or with respect toother examples (or one or more aspects thereof) shown or describedherein.

In the event of inconsistent usages between this document and anydocuments so incorporated by reference, the usage in this documentcontrols.

In this document, the terms “a” or “an” are used, as is common in patentdocuments, to include one or more than one, independent of any otherinstances or usages of “at least one” or “one or more.” In thisdocument, the term “or” is used to refer to a nonexclusive or, such that“A or B” includes “A but not B,” “B but not A,” and “A and B,” unlessotherwise indicated. In this document, the terms “including” and “inwhich” are used as the plain-English equivalents of the respective terms“comprising” and “wherein.” Also, in the following claims, the terms“including” and “comprising” are open-ended, that is, a system, device,article, composition, formulation, or process that includes elements inaddition to those listed after such a term in a claim are still deemedto fall within the scope of that claim. Moreover, in the followingclaims, the terms “first,” “second,” and “third,” etc. are used merelyas labels, and are not intended to impose numerical requirements ontheir objects.

Geometric terms, such as “parallel”, “perpendicular”, “round”, or“square”, are not intended to require absolute mathematical precision,unless the context indicates otherwise. Instead, such geometric termsallow for variations due to manufacturing or equivalent functions. Forexample, if an element is described as “round” or “generally round”, acomponent that is not precisely circular (e.g., one that is slightlyoblong or is a many-sided polygon) is still encompassed by thisdescription.

The above description is intended to be illustrative, and notrestrictive. For example, the above-described examples (or one or moreaspects thereof) may be used in combination with each other. Otherembodiments can be used, such as by one of ordinary skill in the artupon reviewing the above description. The Abstract is provided to complywith 37 C.F.R. § 1.72(b), to allow the reader to quickly ascertain thenature of the technical disclosure. It is submitted with theunderstanding that it will not be used to interpret or limit the scopeor meaning of the claims. Also, in the above Detailed Description,various features may be grouped together to streamline the disclosure.This should not be interpreted as intending that an unclaimed disclosedfeature is essential to any claim. Rather, inventive subject matter maylie in less than all features of a particular disclosed embodiment.Thus, the following claims are hereby incorporated into the DetailedDescription as examples or embodiments, with each claim standing on itsown as a separate embodiment, and it is contemplated that suchembodiments can be combined with each other in various combinations orpermutations. The scope of the invention should be determined withreference to the appended claims, along with the full scope ofequivalents to which such claims are entitled.

1. (canceled)
 2. A medical device seal assembly comprising: a housing; afirst seal at least a portion of which is inside the housing and has aside wall, an interior chamber defined by the side wall, a seal portionconnected to the side wall, and a seal opening defined in the sealportion; and a seal expander arranged in the first seal and having aplurality of elongated segments, wherein: the plurality of elongatedsegments extends into the interior chamber of the first seal to convergeat an intermediate neck and define a minimum internal dimension of theneck and then diverge to a distal mouth and define a second minimuminternal dimension of the distal mouth larger than the minimum internaldimension of the neck; and each elongated segment of the plurality ofelongated segments has a first radial thickness that is larger at theneck than a second radial thickness at the mouth.
 3. The medical deviceseal assembly of claim 2, wherein: the minimum internal dimension of theneck is less than an outer cross-sectional dimension of an instrumentshaft such that the instrument shaft is configured to be insertedthrough the plurality of elongated segments and to bias the plurality ofelongated segments outward to press against the side wall of the firstseal.
 4. The medical device seal assembly of claim 2, wherein: theplurality of elongated segments are arranged concentrically around theaxis of the interior chamber.
 5. The medical device seal assembly ofclaim 2, further comprising a second seal and an extraction guide,wherein: the second seal is distal of the first seal; the extractionguide is between the first seal and the second seal; at least a portionof the extraction guide is inside the second seal; and at least aportion of the first seal is inside the extraction guide.
 6. The medicaldevice seal assembly of claim 5, wherein: the extraction guide comprisesa distally-facing concave surface and an extraction guide opening in thedistally-facing concave surface; and the extraction guide opening isaligned with the seal opening of the first seal.
 7. The medical deviceseal assembly of claim 2, wherein: for each elongated segment of theplurality of elongated segments, a distal tip is positioned on or nearthe side wall of the first seal.
 8. The medical device seal assembly ofclaim 2, further comprising a base portion, wherein: each elongatedsegment of the plurality of elongated segments is coupled to the baseportion by one or more hinge portions and pivots at the one or morehinge portions when the neck is expanded.
 9. The medical device sealassembly of claim 2, further comprising: a cannula cap; a cannulacoupled to the cannula cap; and a second seal at least partially in thecannula.
 10. The medical device seal assembly of claim 2, wherein: theseal opening is circular and has a seal opening diameter; the minimuminternal dimension of the neck is a minimum inner diameter of the neck;and the seal opening diameter is smaller than the minimum internaldiameter of the neck.
 11. The medical device seal assembly of claim 10,wherein: the seal opening diameter is expandable to accommodate a rangeof diameters of shafts configured to be inserted through the sealopening; the inner diameter of the neck is expandable to accommodate therange of diameters of shafts configured to be inserted though theplurality of elongated segments; a difference between the seal openingdiameter and the inner diameter of the neck defines a seal offsetdimension; and the plurality of elongated segments are sized and shapedto provide a consistent seal offset dimension for the range of diametersof shafts.
 12. The medical device seal assembly of claim 2, wherein: ina first state, the seal opening and the plurality of elongated segmentsare each in a neutral state, and a difference between a diameter of theseal opening and an inner diameter of the neck defines a neutral stateoffset dimension; and in a second state, the seal opening and theplurality of elongated segments are each in an expanded state toaccommodate a shaft portion of an instrument, and a difference betweenthe diameter of the seal opening and the inner diameter of the neckdefines an expanded state offset dimension approximately the same as theneutral state offset dimension.